In death, a main fear is being forgotten. Cultures all throughout history have went to great lengths to ensure that their rulers and family members would be remembered through magnificent pyramids, elaborate entombments, and even humble limestone grave markers. Stones were used for their permanence and normally, stones last well in nature. However, beginning in the 1950s rainfall has been altered slightly than that of days of old due to pollutants being released into the atmosphere (1). This “new” rain has a destructively low pH which has progressively increased with the decades. Aside from the numerous negative impacts on farming and soil structure, acidic rain brings transience to many grave markers. Through redox and acid base chemistry, the rain interacts with limestone, marble, bronze, and many other materials to slowly destroy the headstones. Some rates suggest weathering amounting to 56g/year of tombstone loss due to acid rain (2) 
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Rain Vs. Tombstones 